Ratchet hand tool



June 9, 1964 J. KARL ETAL RATCHET HAND TOOL Filed May 14, 1962 u a OLM 1 N WRM A I T M m T A u EN 4W. 50 0| J5 W FIG.5

United States Patent 3,136,346 RATCHET HAND T0013 Joseph M. Karl and Sidney For-man, Washington, N.J., assignors to Gawall Tool Co., Ltd., New York, N.

a corporation of New York Filed May 14, 1962, Ser. No. 194,293 1 Claim. (Cl. 14574) The present invention relates to hand tools and more especially to a socket wrench or screw driver having an improved ratchet drive which can be readily adjusted by the operator.

Hand tools provided with a ratchet drive have long since been known to the art. However, in substantially every instance adjustment of the ratchet to change the direction of working movement of the tool has required theuse of both hands. Moreover, the design of the ratchet arrangement itself has heretofore been such that upon wear of any of the moving parts it was diflicult if not impossible to-disassemble the mechanism and replace such parts thus resulting in the complete disposal of the tool.

It is accordingly the primary object of the present invention to provide a hand tool having a ratchet arrangement and wherein the latter can be readily adjusted by the thumb of the operator while the tool is held in one hand.

Another object of the present invention is the provision of a hand tool having a ratchet drive arrangement which is rapidly assembled in the tool and which can be just as readily disassembled to enable replacement of any worn parts.

Still further objects of the present invention will become obvious to those skilled in the art by reference to the accompanying drawing wherein:

FIGURE 1 is an elevational view of a hand tool in the form of a pistol-grip screw driver made in accordance with the present invention,

FIG. 2 is a fragmentary top plan view of the screw driver as shown in FIG. 1,

FIG. 3 is a sectional view on an enlarged scale taken on the line IIIIII of FIG. 2 and looking in the direction shown by the arrows,

FIG. 4 is a sectional view taken on the line IV-IV of FIG. 3 and looking in the direction indicated by the arrows,

FIG. 5 is a sectional view taken on the line V-V of FIG. 3 and also looking in the direction indicated by the arrows,

FIG. 6 is a broken perspective view of the movable plunger forming a part of the ratchet arrangement of present invention, and

FIG. 7 is a fragmentary plan view showing the interconnection between the end of the ratchet plunger or pawl and the ratchet block.

Referring now to the several figures of the drawing which disclose one form which the present invention may take, the particular hand tool as shown in FIG. 1 comprises a pistol-grip screw driver wherein the handle 5 is disposed substantially at right angles to the operating shank 6, which may carry at its outer end a tool receiving chuck 4 (FIG. 3) or be directly provided with a screw driver blade 7 (FIG. 1). As shown more particularly in FIG. 3 the shank 6 is permarnently keyed to a ratchet block 8 rotatably disposed in a recess 9 provided in the handle 5. Coaxially disposed relative to this recess 9 is a longitudinal bore 10 extending through the handle 5 to a rear recess 12 for the accommodation of the innermost portion of the shank 6. A locknut or the like 13 is disposed on the extreme inner end of the shank 6 for the purpose of holding the latter, together with its integral ratchet block 8, in the recess 9 and bore 10, respectively, and yet allows rotation thereof as a unit relative to the handle 5.

The rear surface of the ratchet block 8, as seen in FIGS.

3,135,346 Patented June 9, 1964 "ice - 5 and 7, is provided with a plurality of radially extending channels or grooves 14 thus providing segmental. sections 15 and a smaller diameter bore 16 parallel to the axial bore 10' also extends through the handle 5 from the foremost recess 9 to the rear recess 12. A plunger having an angular end thus forming a pawl 17 is disposed for rotational and longitudinal movement within this smaller bore 16 and at its opposite end is of slightly reduced diameter to accommodate a surrounding coil spring 18. In order to hold this coil spring 18 properly in place and to form a sliding end bearing 19 for the pawl plunger 17, the handle 5 is provided with a pocket 20in areadily removable end cap 21 and normally held in place by a recessed screw 22 which also forms a closure for the rear handle recess 12.

An operating wheel or collar 23, provided with a knurled edge if desired, is carried by the pawl plunger 17 near the spring-supported end which is of suificient diameter so as to project through a slot 24 in the handle 5. As can be seen more clearly from FIG. 4 this presents a segmental portion extending above the top surface of the handle 5 so that the operator can readily rotate the collar 23 with his thumb or finger in either direction while holding the tool in the same hand; Rotation of the operating collar 23 causes simultaneous rotation of the pawl plunger 17 due to a proper key connection therebetween and at the same time allows longitudinal movement of the pawl plunger 17 within the bore 16 through a loost fit between the pawl plunger and collar. Although any well known key arrangement may be used it has been found most economical to form the pawl plunger 17 from hexagonal stock and to punch a central opening in the collar 23 of the same configuration with sufi'icient clearance to allow sliding movement therebetween.

This accordingly causes rotation of the pawl plunger 17 to accurately follow rotation of the collar 23 under control of the operator. Consequently, when an indicator, such as an embossment or notch 25 (FIG. 4), in the edge of the collar 23 is aligned with the letter N (no ratchet) on the handle 5 (FIG. 2) the pawl plunger 17 will be rotated to orientate its angular end so that it then lies in a plane perpendicularly disposed relative to the side walls of channel 14 formed by the segments 15. The rounded surface of the angular end of pawl plunger 17 will therefore contact the channel walls, as shown in FIG. 3, effectuating a direct drive so that when the operator turns the handle 5 in either direction to drive or loosen a screw the blade 7 directly follows movement of the handle.

When the operator turns the notch 25 to align with the letter L on the handle 5 the pawl plunger 17 is rotated about (from the position shown in either FIG. 3 or FIG. 6) within the bore 16 and bearing 19, to dispose the angular end thereof in a plane converging with one of the walls of channel 14 while a rounded portion of the end bears against the opposite channel wall, as shown in FIG. 7. This enables the hand tool to be turned to the right or clockwise to drive in a screw by a direct connection but when the handle 5 is turned to the left or counter-clockwise it will ratchet to the left (L). This is due to the angular end riding on the shoulder 26 formed at the converging of the angular end with the left hand channel 14 (FIG. 7) which thus forces the pawl plunger 17 longitudinally of the bore 16 and bearing 19 against the pressure exerted by spring 18, allowing the handle to rotate about the stationary shank 6 engaging the screw, with the angular end of the pawl plunger 17 riding over the end of the ratchet block 8 and into one channel 14 after the other so long as the tool is turned counter-clockwise.

Likewise when it is desired to loosen or remove a screw or the like with the aid of ratcheting, the operator merely uses his thumb to rotate the collar 23 to align the notch 25 with the letter R on the top of the handle 5. Such movement then positions the angular end of the pawl plunger 17 in a position one hundred and eighty degrees from that shown in FIG. 7, with the same ratcheting operation following as above-mentioned except that the hand tool would directly drive the screw when turned counterclockwise and ratchet to the right (R) when the handle 5 is rotated clockwise. A spring-pressed ball 26 (FIG. 3) fitting into an indentation (FIG. 4) provided on the rear surface of the collar 23 retains the latter together with the pawl plunger in its selected N, R, or L position.

From the foregoing it should become obvious to those skilled in the art that a hand tool is herein provided having a completely enclosed ratchet arrangement and wherein operation of such totally housed ratchet is eifec'ted by the operator merely using his thumb to rotate slightly in either desired direction a collar having only a small seg ment of its circumference protruding outside the handle. Moreover, the end closure for the hand tool can be readily removed to allow for quick and easy replacement of any Worn parts and immediately replaced merely by manipulation of the single assembling screw.

Although one specific embodiment of the present invention has been herein shown and described it is to be understood that other modifiactions thereof may be made without departing from the spirit and scope of the appended claim:

We claim:

A ratchet hand tool comprising:

(a) a handle having an axial bore interconnecting a larger diameter recess in the front with a similar recess at the rear of said handle,

(b) a tool shank rotatably supported in said bore and extending outwardly of the front recess in said handle,

(0) a ratchet block provided with a plurality of channels secured to said shank and rotatable in the front recess of said handle upon rotation of said shank,

(d) a second longitudinal bore in said handle parallel 4 to said first bore and extending from the front recess to the rear recess therein,

(e) a non-circular pawl plunger supported in said second bore for rotational and longitudinal movement and provided with an angular end and a biasing means at its other end for forcing the angular end of said pawl plunger into engagement with the channels of said ratchet block,

(f) an arcuate slot in said handle perpendicular to said second bore and communicating with the rear recess in said handle,

(g) a collar slidably keyed to said pawl plunger with a segment of said collar projecting through said slot and slightly above the surface of said handle for rotation of said pawl plunger in either direction by the thumb or finger of an operator to cause the angular end of said pawl to engage one of the channels of said ratchet block in one position or an opposite position to provide selected directional ratcheting of said hand tool and said collar being also operable to rotate said pawl to a still further position to lock the end of said pawl plunger in a channel of said ratchet block against ratcheting when desired,

(h) and a detachable end cap for closing the rear recess in said handle and provided with a recess en gageable by a portion of said collar to form a hearing surface therefor as well as a pocket for the biasing means at the end of said pawl plunger and said end cap having a biased detent engaging said collar to prevent inadvertent rotation thereof.

References Cited in the file of this patent UNITED STATES PATENTS 256,351 McGregor Apr. 11, 1882 828,440 Sullivan Aug. 14, 1906 1,506,547 Peyer Aug. 27, 1924 1,618,428 Harwood et a1 Feb. 22, 1927 2,989,881 Lavietes June 27, 1961 

